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** Copyright (C) 2008-2012 NVIDIA Corporation.
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
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** This file is part of Qt 3D Studio.
**
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** the Free Software Foundation and appearing in the file LICENSE.GPL3
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#pragma once
#ifndef QT3DS_RENDER_QUERY_BASE_H
#define QT3DS_RENDER_QUERY_BASE_H
#include "foundation/Qt3DSRefCounted.h"
#include "foundation/Qt3DSFoundation.h"
#include "foundation/Qt3DSBroadcastingAllocator.h"
#include "foundation/Qt3DSAtomic.h"
#include "render/Qt3DSRenderBaseTypes.h"
#include "render/backends/Qt3DSRenderBackend.h"

namespace qt3ds {
class NVFoundationBase;
}

namespace qt3ds {
namespace render {

    // forward declaration
    class NVRenderContextImpl;
    class NVRenderBackend;

    ///< Base class
    class NVRenderQueryBase : public NVRefCounted
    {
    protected:
        NVRenderContextImpl &m_Context; ///< pointer to context
        NVFoundationBase &m_Foundation; ///< pointer to foundation
        volatile QT3DSI32 mRefCount; ///< Using foundations' naming convention to ease implementation
        NVRenderBackend *m_Backend; ///< pointer to backend
        NVRenderBackend::NVRenderBackendQueryObject m_QueryHandle; ///< opaque backend handle

    public:
        /**
         * @brief constructor
         *
         * @param[in] context		Pointer to context
         * @param[in] fnd			Pointer to foundation
         *
         * @return No return.
         */
        NVRenderQueryBase(NVRenderContextImpl &context, NVFoundationBase &fnd);

        virtual ~NVRenderQueryBase();

        // define refcount functions
        QT3DS_IMPLEMENT_REF_COUNT_ADDREF_RELEASE(m_Foundation)

        /**
         * @brief Get query type
         *
         * @return Return query type
         */
        virtual NVRenderQueryType::Enum GetQueryType() const = 0;

        /**
         * @brief Get a pointer to the foundation
         *
         * @return pointer to foundation
         */
        NVFoundationBase &GetFoundation() { return m_Foundation; }

        /**
         * @brief begin a query
         *
         * @return no return.
         */
        virtual void Begin() = 0;

        /**
         * @brief end a query
         *
         * @return no return.
         */
        virtual void End() = 0;

        /**
         * @brief Get the result of a query
         *
         * @param[out] params	Contains result of query regarding query type
         *
         * @return no return.
         */
        virtual void GetResult(QT3DSU32 *params) = 0;

        /**
         * @brief get the backend object handle
         *
         * @return the backend object handle.
         */
        virtual NVRenderBackend::NVRenderBackendQueryObject GetQuerytHandle() const
        {
            return m_QueryHandle;
        }
    };
}
}

#endif